Microelectronic chip integration technology has lead to recent improvements. In the past, electronic systems have required the use of multi-chip systems including many microchips and discrete components. However, as integrated circuit technology has advanced, systems-on-chip (SOCs) have become more popular. A single SOC may contain, for example, numerous digital and analog integrated circuit components, e.g. CPUs, memories, random logic, RF circuitry, etc. Circuits of the type described above (i.e. mixed signal circuits that integrate various digital and analog circuit blocks on an SOC) present certain challenges. For example, a signal in one circuit may disrupt a signal in an adjacent circuit. This undesirable electrical interaction may be referred to as noise and/or crosstalk that may occur due to inductive or capacitive coupling.
It is well known to provide SOCs with contact pads that are ESD (electrostatic discharge) protected. Unfortunately, in some cases, noise can propagate via the ESD protected pads through the substrate and hamper the performance of sensitive circuitry on the SOC.
Thus, it would be desirable to provide a method for improving substrate noise isolation between ESD protected pads, circuit biasing lines and the SOC circuitry. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.